The RNA Processing Meeting provides an annual forum for researchers to share recent findings about RNA splicing and other RNA processing reactions, RNA catalysis, structure-function relationships in RNA and RNA-protein complexes, regulation at the level of alternative RNA processing and RNA editing and modification. The meetings have attracted an extraordinarily broad spectrum of scientists, including biochemists, molecular biologists, chemists, geneticists and cell biologists. A continuation of these meetings is proposed for 1991-1993. The organizer will select session chairmen and organize the meeting into 7 or 8 scientific sessions Plus 3 poster sessions. Speakers will be chosen from the abstracts submitted. Poster sessions will provide all conferees with an opportunity to present their work, and will not be limited. Past meetings have shown that the face-to-face contact engendered by this format enhances the quality and rate of progress in this field, promotes collaborative interactions, and ensures that the most up-to-date methods for analysis of RNA are communicated promptly. This is the only meeting dedicated to this rapidly-moving area of research that is held on an annual basis. The problems to be clarified by the Cold Spring Harbor RNA Processing Meeting include the pathway of assembly of the large complexes in which nuclear mRNA splicing takes place; the roles of individual small nuclear RNPs and proteins in splicing and other processing reactions; the mechanisms of trans-splicing; the role of RNA catalysis in a variety of steps in the maturation of tRNA, rRNA and mRNA; and the mechanisms of RNA editing and modification.